/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkFontMgr_DEFINED
#define SkFontMgr_DEFINED

#include "include/core/SkRefCnt.h"
#include "include/core/SkTypes.h"

#include <memory>

class SkData;
class SkFontStyle;
class SkStreamAsset;
class SkString;
class SkTypeface;
struct SkFontArguments;

class SK_API SkFontStyleSet : public SkRefCnt {
public:
    virtual int count() = 0;
    virtual void getStyle(int index, SkFontStyle *, SkString *style) = 0;
    virtual sk_sp<SkTypeface> createTypeface(int index) = 0;
    virtual sk_sp<SkTypeface> matchStyle(const SkFontStyle &pattern) = 0;

    static sk_sp<SkFontStyleSet> CreateEmpty();

protected:
    sk_sp<SkTypeface> matchStyleCSS3(const SkFontStyle &pattern);
};

class SK_API SkFontMgr : public SkRefCnt {
public:
    int countFamilies() const;
    void getFamilyName(int index, SkString *familyName) const;
    sk_sp<SkFontStyleSet> createStyleSet(int index) const;

    /* *
     * The caller must call unref() on the returned object.
     * Never returns NULL; will return an empty set if the name is not found.
     *
     * Passing nullptr as the parameter will return the default system family.
     * Note that most systems don't have a default system family, so passing nullptr will often
     * result in the empty set.
     *
     * It is possible that this will return a style set not accessible from
     * createStyleSet(int) due to hidden or auto-activated fonts.
     */
    sk_sp<SkFontStyleSet> matchFamily(const char familyName[]) const;

    /* *
     * Find the closest matching typeface to the specified familyName and style
     * and return a ref to it. The caller must call unref() on the returned
     * object. Will return nullptr if no 'good' match is found.
     *
     * Passing |nullptr| as the parameter for |familyName| will return the
     * default system font.
     *
     * It is possible that this will return a style set not accessible from
     * createStyleSet(int) or matchFamily(const char[]) due to hidden or
     * auto-activated fonts.
     */
    sk_sp<SkTypeface> matchFamilyStyle(const char familyName[], const SkFontStyle &) const;

    /* *
     * Use the system fallback to find a typeface for the given character.
     * Note that bcp47 is a combination of ISO 639, 15924, and 3166-1 codes,
     * so it is fine to just pass a ISO 639 here.
     *
     * Will return NULL if no family can be found for the character
     * in the system fallback.
     *
     * Passing |nullptr| as the parameter for |familyName| will return the
     * default system font.
     *
     * bcp47[0] is the least significant fallback, bcp47[bcp47Count-1] is the
     * most significant. If no specified bcp47 codes match, any font with the
     * requested character will be matched.
     */
    sk_sp<SkTypeface> matchFamilyStyleCharacter(const char familyName[], const SkFontStyle &, const char *bcp47[],
        int bcp47Count, SkUnichar character) const;

    /* *
     * Create a typeface for the specified data and TTC index (pass 0 for none)
     * or NULL if the data is not recognized. The caller must call unref() on
     * the returned object if it is not null.
     */
    sk_sp<SkTypeface> makeFromData(sk_sp<SkData>, int ttcIndex = 0) const;

    /* *
     * Create a typeface for the specified stream and TTC index
     * (pass 0 for none) or NULL if the stream is not recognized. The caller
     * must call unref() on the returned object if it is not null.
     */
    sk_sp<SkTypeface> makeFromStream(std::unique_ptr<SkStreamAsset>, int ttcIndex = 0) const;

    /* Experimental, API subject to change. */
    sk_sp<SkTypeface> makeFromStream(std::unique_ptr<SkStreamAsset>, const SkFontArguments &) const;

    /* *
     * Create a typeface for the specified fileName and TTC index
     * (pass 0 for none) or NULL if the file is not found, or its contents are
     * not recognized. The caller must call unref() on the returned object
     * if it is not null.
     */
    sk_sp<SkTypeface> makeFromFile(const char path[], int ttcIndex = 0) const;

    sk_sp<SkTypeface> legacyMakeTypeface(const char familyName[], SkFontStyle style) const;

    /* Returns an empty font manager without any typeface dependencies */
    static sk_sp<SkFontMgr> RefEmpty();

protected:
    virtual int onCountFamilies() const = 0;
    virtual void onGetFamilyName(int index, SkString *familyName) const = 0;
    virtual sk_sp<SkFontStyleSet> onCreateStyleSet(int index) const = 0;

    /* * May return NULL if the name is not found. */
    virtual sk_sp<SkFontStyleSet> onMatchFamily(const char familyName[]) const = 0;

    virtual sk_sp<SkTypeface> onMatchFamilyStyle(const char familyName[], const SkFontStyle &) const = 0;
    virtual sk_sp<SkTypeface> onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle &,
        const char *bcp47[], int bcp47Count, SkUnichar character) const = 0;

    virtual sk_sp<SkTypeface> onMakeFromData(sk_sp<SkData>, int ttcIndex) const = 0;
    virtual sk_sp<SkTypeface> onMakeFromStreamIndex(std::unique_ptr<SkStreamAsset>, int ttcIndex) const = 0;
    virtual sk_sp<SkTypeface> onMakeFromStreamArgs(std::unique_ptr<SkStreamAsset>, const SkFontArguments &) const = 0;
    virtual sk_sp<SkTypeface> onMakeFromFile(const char path[], int ttcIndex) const = 0;

    virtual sk_sp<SkTypeface> onLegacyMakeTypeface(const char familyName[], SkFontStyle) const = 0;
};

#endif
